COMPARATIVE STUDY OF SUNFLOWER LATE–SPRING MIXTURES FOR FORAGE PRODUCTION IN A FOOTHILL REGION OF CENTRAL BALKAN MOUNTAINS (BULGARIA)

Abstract

During the 2013-2014 period in the Research Institute of Mountain Stockbreeding and Agriculture (RIMSA) in Troyan (Bulgaria) a comparative study of sunflower late-spring mixtures for green forage production was carried out. For this purpose were studied mixtures with legume forage crop (spring field peas) and some cereal species (spring oats, maize and sorghum-sudan grass). It was found that the most productivity (6.31 t.ha(-1) green mass and 1.34 t.ha(-1)dry mass) was prepared from the mixture of sunflower and maize, which is more respectively with 85.04 and 162.75 % compared to the sunflower monoculture (Standard). The yields excess in the other studied mixtures was less and ranged from 5.87 to 25.22 % for the green mass and from 21.57 to 68.63 % for the dry matter. Regardless of the various components, in the sunflower pure and mixed crops the weed infestation was a relatively low, and it had no significant influence of the forage quality.